1. Field of the Invention
The present invention relates to a coordinate calculator and a coordinate calculation system.
2. Description of the Related Art
An interactive white board (hereinafter referred to as an IWB) is known that receives touch interactions, handwriting, and others. Examples of the IWB include an optical IWB employing a camera sensor.
Japanese Unexamined Patent Application Publication No. 2000-089913 describes calibration of a touch panel input coordinate transformation device. With the technique of Japanese Unexamined Patent Application Publication No. 2000-089913 using a calibration application, a mark image for calibration is displayed on a display device. When the mark is pressed with a finger, a pen, or the like, coordinates detected through the touch panel is transmitted to an operating system (OS) of a personal computer (PC). The PC performs calibration using the coordinates and coordinates of the mark image.
However, such a conventional technique is supposed to use an IWB with a built-in PC and causes the built-in PC to perform all calculation including coordinate calculation, drawing processing using the calculated coordinates, calibration, and others. This configuration problematically restricts a reduction in size of the device. To overcome the problem, such a method is employed that causes hardware (for example, a small digital signal processor (DSP)) to perform constantly necessary coordinate calculation and causes a connected external PC to perform correction calculation such as calibration used in a limited opportunity, for example, in setting up the device. With the method, however, dedicated hardware is controlled by the connected external PC, and thus development of a dedicated driver and installation thereof on the connected external PC are required.
From the above-described viewpoints, there is a need to provide a coordinate calculator and a coordinate calculation system easily configured even when processing relating to coordinate calculation is executed by the dedicated hardware.